The present invention generally relates to a body structure for a motor vehicle and more particularly, to an improvement of a rear body structure for a motor vehicle such as an automobile or the like.
Conventionally, as a rear body structure for an automobile, the Japanese Laid-open Utility Model Publication No. 55-124369 discloses an improved rear side frame wherein the rear side frame which extends in a longitudinal direction of an automobile body on each side of the rear portion thereof is generally formed in a shape similar to that of a figure "Y" at the front side of the rear side frame in order to increase the rigidity thereof.
Meanwhile, in the rear body structure as shown in FIG. 1, a rear suspension 5 is mounted on the rear side frame 1 through a suspension arm 2, a damper 3 and the like for supporting a rear tire 4, and a spring 6 for the rear suspension 5, which is disposed on the lower surface of the rear side frame 1. The rear side frame 1 is required to be formed thin in thickness in a vertical direction at a portion thereof on which the spring 6 is mounted, rather than other portions, for ensuring a sufficient length of the spring 6, thus undesirably resulting in such a drawback as the rear side frame 1 has been decreased in rigidity.